In order to obtain uniform heating in a microwave oven, not only is it desirable to provide a wave spreader, it is also desirable to stir the substance contained in the receptacle.
In French patent number 2 588 063 the Applicant has already proposed a solution consisting in providing a microwave oven including a moving sole plate enabling the height at which the substance in the receptacle is stirred to be adjusted at will. However, using an oven with a moving sole plate requires an installation which is large in size and which is not necessary when small and medium quantities of substance are to be treated.
An object of the present invention is to provide a stirrer whose structure enables it to be used in an oven which is small in size.